Could the biology of violent behavior have played a role in the bombings?

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Boston Marathon bombing suspect Tamerlan Tsarnaev probably never imagined leaving his brain to science. But we should suggest the idea to whomever has custody of his remains. Neuroscientists should be given the chance to examine his brain closely.

Consider the story of Charles Whitman. In the early hours of Aug. 1, 1966, he killed his mother, and then his wife. Later that morning, he got organized and purchased firearms and ammunition and brought them, along with his sniper’s skill, to the top of a tower at the University of Texas in Austin. He began shooting and — by the time an Austin policeman’s bullets put him down — he had killed 17 people and wounded 32 others. In the 24 hours before the end of his siege, Whitman wrote several notes, including one requesting an autopsy to determine whether or not something was wrong with his brain.

Something was. The medical examiner found a small tumor pressing on a brain region, the amygdala, known to regulate emotion.

Since the Marathon bombings, we have been reading reports of the radicalization of Tamerlan Tsarnaev, the older of the two bombing suspects. But we have also read reports of his anger and intensity. He had attracted local attention as a boxer and was a martial arts enthusiast. A local imam has described angry disruptions at a Cambridge mosque. In 2009, Tsarnaev faced domestic violence charges that were later dismissed.

Another news report has the community wondering whether Tsarnaev had a hand in the 2011 murder of three men in Waltham, one of whom he had called his “best friend.”

We are hungry for details that could explain why two young men would be driven to maim and kill. But a string of reports, many of which are second- and thirdhand, do not make a coherent explanation. Sensible people will wait months and years for a reliable account to emerge.

The driving narrative, the one garnering the most national attention, is about radicalization and the influence of an alien culture set on terrorizing us. Curiosity has turned usefully to the aspects of politics and culture, or of social and family life, that may breed violent behavior.

Getting less attention is the biology of violent behavior. One case is not going to satisfy our curiosity, but we do have an opportunity now to examine important and interesting evidence that is there for the taking.

So yes, let’s study Tsarnaev’s brain.

Dr. Robert Cantu and Dr. Robert Stern of Boston University’s Center for the Study of Chronic Traumatic Encephalopathy have already expressed their interest in examining it. Tsarnaev’s high-level participation in boxing may have exposed him to multiple head knocks. In other words, he may have endured repetitive head injury and developed the brain disease that BU’s experts have studied in football players and other athletes.

We are not likely to agree about the meaning of what is found in the brain of the suspected bomber. The pathologist who discovered Charles Whitman’s tumor said it was not related to his violent tear. He called Whitman a psychopath of the worst kind. Cantu and Stern point out that, even if Tsarnaev shows evidence of chronic traumatic encephalopathy or some other pathology, it would not necessarily have been the cause of Tsarnaev’s premeditated, violent behavior.

But where does psychopathy come from if not the brain? The brain is, after all, the mediator of all thought and behavior. And this suspect’s brain may teach us a small but important bit about the biology of violence.

So our local experts should get the chance to study Tamerlan Tsarnaev’s brain. And they should study it as closely as our forensic experts have studied a few blocks along Boylston Street.

Dr. Michael Craig Miller is former editor-in-chief of the Harvard Mental Health Letter and a psychiatrist at Beth Israel Deaconess Medical Center.